If you were, you know, living your lives, you've probably missed it, but old fires are burning brightly once again: there's somewhat of a falling-out going on between KDE and GNOME, with Canonical siding squarely with... KDE. The issue seems to revolve around GNOME's lack of collaboration, as explained by KDE's Aaron Seigo.

The truth is we had then and even more now many many examples of applications that quite successfully separate data from presentation in the systray. The vast majority of these aren't new fandangled apps, but legacy apps that were easily updated to support the features made available by the spec. In fact for apps that weren't updated, all current implementations of the spec fall back to the old XEmbed behaviour - they behave as they always have. The actual implemenations of the spec (KDE, Unity and Cairo-Dock) demonstrate quite clearly that, not only can it be done but it works quite well.